Kinetic parameter calculation for predicting advanced fuel combustion via transition state theory

Abstract

Rising oil prices and concerns about climate change motivate the need for new and renewable fuel sources. New engine designs will be required to use these fuels in an efficient manner, and detailed kinetic models can reduce the engine design costs by reducing the need for expensive engine tests. Key to these detailed models are the rate parameters, but experimental difficulties mean a small percentage have been accurately determined. Estimation methods bridge the gap, but better predictions of these rate constants can be calculated by applying transition state theory for important reactions . Detailed kinetic model generators, such as Reaction Mechanism Generator, require an automated method to find transition state geometries in order to apply the theory. We propose to do so by specifying minimum and maximum distances between every atom so that the reactants and products are in a reactive state, then use distance geometry to find a 3D geometry that satisfies those bounds. This novel approach will enable interpolation between these geometries, and optimization to find the transition state structure without manual inputs.